The present invention involves energy recovery from shower greywater. In particular, the invention relates to a system for heat exchanger based heat recovery from shower greywater, and cleaning of heat exchangers in shower greywater heat recovery applications.
The amount of energy that is flushed down the drain and wasted in ordinary showers is relatively large compared to other power consuming devices on the consumer market. A standard shower consumes a power of about 8 to 30 kW, depending on the temperature and flow of shower greywater. Therefore, there is a significant potential to reduce the hot supply water usage (and energy consumption) in households by using the heat in the relatively hot shower greywater to heat up the cold water before the hot supply water reaches the shower mixer. A number of solutions for energy recovery from shower greywater are described in literature. See for example, foreign and US patents numbered GB2232749, U.S. Pat. No. 4,619,311 and GB2052698.